Controller systems, such as those including microprocessors, frequently require analog inputs in order to perform the necessary control functions. By way of example, a microprocessor may be configured to receive multiple signals from analog sensors, with the resultant controls being at least partially based on the received signals. However, as is generally known in the art, microprocessors operate using digital data. In order to accommodate the analog signals, analog to digital converters are commonly used.
Further, in some systems various functionalities of the microprocessor are tested by providing a known analog input to a given input pin. This is commonly achieved through the usage of a stimulation circuit connected to an analog input and configured to cause the analog input to have a specific, predefined, value when the stimulation circuit is activated. However, in existing controllers operation and control of a stimulation circuit requires substantial software overhead by the microprocessor, and can limit the ability of the microprocessor to perform other tasks related to the controls.